Balanced chemical reaction happening here is:
3Mg(s) + N₂(g) → Mg₃N₂(s)
<u>moles of product formed from each reactant:</u>
2.0 mol of N2 (g) x <u> 1 mol Mg₃N₂ </u> = <u>2 mol Mg₃N₂</u>
1 mol N2
and
8.0 mol of Mg(s) x <u> 1 mol Mg₃N₂ </u> = 2.67 mol Mg₃N₂
3 mol Mg
Since N2 is giving the least amount of product(Mg₃N₂) ie. 2 mol Mg₃N₂
N2 is the limiting reactant here and Mg is excess reactant.
Hence mole of product formed here is 2 mol Mg₃N₂
molar mass of Mg₃N₂
= 3 Mg + 2 N
= 101g/mol
mass of product(Mg₃N₂) formed
= moles x Molar mass
= 2 x 101
= 202g Mg₃N₂
<u>202g of product are formed from 2.0 mol of N2(g) and 8.0 mol of Mg(s).</u>
<u> </u> The following are indicators of chemical changes:
Change in Temperature
Change in Color
Formation of a Precipitate
Answer:
A soap or alcohol will interfere with the hydrogen bonding between water molecules making it weaker
Explanation:
A water molecule is polar as the oxygen atom is strongly electronegative and draws the electrons it shares with the hydrogen atoms in the water molecule to itself. This creates a partial negative charge on the oxygen atom and partial positive charges on the hydrogen atoms. The attraction of neighboring oxygen to hydrogen atoms in a water molecule results in hydrogen bonding.
However, a detergent molecule which has a polar head and a hydrophobic tail, when added to water significantly interferes with the hydrogen bonding between water molecules. The polar head is attracted to water molecules whereas the hydrophobic tail of each molecule are not. The detergent molecules form clusters known as micelles with the polar heads attracted to water and the hydrophobic tails directed towards the center of the micelle, away from water molecules. This weakens the hydrogen bonding between water molecules
An alcohol contains a polar -OH group in its molecules. However, the hydrogen bonding between alcohol molecules are weaker than that in water because the other end of the alcohol molecule has a C-O bond which is less polar than the O-H bond. Therefore, when an alcohol is added to water, it weakens the hydrogen bonding in water.
This weakening of the hydrogen bonding in water also has the effect of lowering the surface tension of water.
Answer:
VSEPR theory
Explanation:
The valence shell electron pair repulsion theory was propounded by Gillespie and Nylom (1957).
The entire idea of the VSEPR theory is that the shape of a molecule depends on the electrostatic repulsion between electron pairs surrounding the central atom in a molecule which causes these pairs to be separated as far as possible.
The shapes of many molecules can be accurately predicted based on this model.
Answer:
1.135 M.
Explanation:
- For the reaction: <em>2HI → H₂ + I₂,</em>
The reaction is a second order reaction of HI,so the rate law of the reaction is: Rate = k[HI]².
- To solve this problem, we can use the integral law of second-order reactions:
<em>1/[A] = kt + 1/[A₀],</em>
where, k is the reate constant of the reaction (k = 1.57 x 10⁻⁵ M⁻¹s⁻¹),
t is the time of the reaction (t = 8 hours x 60 x 60 = 28800 s),
[A₀] is the initial concentration of HI ([A₀] = ?? M).
[A] is the remaining concentration of HI after hours ([A₀] = 0.75 M).
∵ 1/[A] = kt + 1/[A₀],
∴ 1/[A₀] = 1/[A] - kt
∴ 1/[A₀] = [1/(0.75 M)] - (1.57 x 10⁻⁵ M⁻¹s⁻¹)(28800 s) = 1.333 M⁻¹ - 0.4522 M⁻¹ = 0.8808 M⁻¹.
∴ [A₀] = 1/(0.0.8808 M⁻¹) = 1.135 M.
<em>So, the concentration of HI 8 hours earlier = 1.135 M.</em>
<span>They have chloroplasts and use light energy to make more food. I think might be wrong </span>
